Coupling device



May 25, 1954 G. JAcoBl ETAL COUPLING DEVICE Filed Sept. 16, 1950 Patented May 25, 1954 Gustav JacobLMnden, Knemann, near Minden Westphalia, and Anton Westphalia, Germany Application September 16, 1950, Serial No`.`185,252 Y Claims priority, application Germany September 19, 1949V This invention relate.; to a coupling for hydraulic pressure pipes, more particularly vfor Athe connection of the oil pressure brake pipe of a motor vehicle to that of its trailer, of the type in which both coupling members comprise springacted check valves which in case of a-closed condition of the coupling are interacting to keep' each other open and on disconnection close automatically by the spring action. The couplings of this kind so far known have the disadvantage that on coupling it may easily happen that air gets into the oil `pressure pipe, whereby as is well known the safety of operation of the whole braking system is endangered.

It is an object of the present invention to provide means in a coupling of the type referred to. for avoiding `this drawback.

With this and further objects in view according to the present invention a coupling member is arranged in a casing containing. a brake fluid and connectable to a pressure pipe, in such a manner that the check valve is v1oelow the level of the brake uid. Provided within the casing is a guide sleeve for the plug member; which sleeve is formed with connecting holes to the casing chamber. l Due to this construction and arrangement the two check valves are alwaysopened below the level of the brake uid present in the coupling case so that penetration of. air into 'the'brake line system is safely prevented. k

In motor vehicles the Vcoupling case is pref-- erably fastened to the truck or motor lorry in the vicinity of the trailer coupling, i. ein such a way that the longitudinal. axis of the coupling case is inclined by about 45 inclination to the vehicle. The plug member on the contrary is connected to a flexible pressure pipe of the braking system of the trailer and after the disconnection-of the coupling is held in a support provided at the trailer. p

Other and further objects, features and advantages of the invention will be pointed 'out hereinafter and appear in the appended claims forming part of the application.

In the accompanying drawings a-nowpreferred embodiment of the invention is shownby way of illustration and not by way of limitation.

, Fig. 1 is a vertical longitudinal section through the coupling in its operative position,

Fig. 2 is a longitudinal section of the plug member, and

Fig. 3 is a longitudinal section through the coupling case.

Similar reference numerals denote similar parts in the different views.

s claims. 01. 284-18) Referring now tov the drawing in greater-de# tail, it will be seen that the coupling casewl` is provided with a cast-on fixing flange 2 forming an angleof about 45 with the longitudinal axis of the case I and serving for securing thecase on a motorl truck. The bottom of the coupling c'aseI is provided with a threaded bore into'which is screwed a valve casing 3 provided with a complementary external thread. Screwed onto lthe end, of the valve casing 3 protruding into the coupling A case I is a cylindrical sleeve or guide tube l serving for guiding the plug member (Fig. 2) and havingits upper end positioned inra central bore of the closing rim 5 of the case. The guide sleeve 4 yis provided with lateral recesses-or holes 6 so that the braking uid is permitted to com# municate within the guide sleeve with the'braking uuid in the casing I,the latter acting as a reservoir for the liquid therein as shown in the drawlngs- Disposed inthe valve casing 3 to which a pressure pipe or duid line 1 is connected in known manner; is aguide cylinder 8 for the carrier 9 Yof the valvehead I0 consisting-ofrubber or a similarrmaterial, members 9 and I0 forming a movable valve member. `Moreover, a compression spring II is disposed in the guide cylinder v:8, which compressing spring acts permanently onto the carrier 9 of the valve head I0. In the 'em-' bodinient illustrated the seat I 2 of the valve'head I I) is provided in the front end of the valve casing 3. The parts 3 and 8'-I2 thus form a `check valve means. The carrier 9 of the valve headY I 0 is provided at fits outer front side with a stem or pin member I3 of such a length that it protrudes in an open positionvof the valve by 'some millimeters 'through the valve seat I2 into the interior of the guide sleeve 4. A

'Th-plug member robe inserted into the sleeve 4vconsistsp-substanuauy of a 'cylindrical body l5 provided with a central bore Ill and havinga valve 'casing 'I B secured to its lower end, which valve `casinglike the valve casing 3 is lprovided with a conical valve seat I'I. Disposed in 'the valve casing I 6 is a guide cylinder I8 for the 'carrier I 9 vof 'the `valve head 2l), which valve head 20 like the valve head "Iii consists-of rubber or a similar material, the members I9 and 20 forming "a movable valve member. The valve head carrier I9 like the carrier `Si is under' permanent action of a compression spring ZI mounted in the guide cylinder I8. Thus, the parts I6-2| form 'a second check valve means. The pin member I3forms a control means for automatically opening both valve means when they are-arranged las shown in Fig. 1`.

Arranged on the upper reduced end I' of the body I5 is a cap member 22 secured against sliding off from its carrier by a spring ring 23. This cap member 22 is provided with a xed stud 24 inwardly projecting from the side wall of member 22, and with a spring-loaded catch pin 25 which is longitudinally slidable in a radial direction. In the coupling operation the xed stud 24 is introduced into an angular or bayonet slot 26 provided at the upper end of the guide sleeve 4, while a bore 28 is provided in the sleeve 4 for the catch pin 25.

The plug member thus constructed is connected to the oil pressure braking system of a truck trailer preferably by means of a flexible pipe 21.

The washer 2S disposed in the guide 4sleeve 4 in the operative position serves for mutually n packing the valve casings 3 and I6.

The operation of the new coupling is very simple. In a disconnected state the springs I I and 2| will force the valve heads I0 and 20 onto their seats I2 and I'I, thus establishing an absolutely tight closure of the two pipes 'I and 21. The casing I and the interior of the guide sleeve 4 are filled with braking fluid to such an extent that the bottom valve 9, Ill, lI, I2, I3 is disposed well below the level of the braking fluid.

On coupling the plug member is introduced into the sleeve 4 of the casing I, displacing the braking uid from the sleeve 4 through the hole 5 into the space outside of the sleeve 4. During the plugging-in operation the valve stem I3 strikes against the carrier I9 of the valve head 20 so that on further moving-in both valve heads are lifted from their seats and both valves mutually keep each other in an open condition. In the end position the washer 29 is xedly urged between the front faces of the valve casings 3 and I6 by the bayonet fixing or swivel connection 24, 26 of the cap 22, thus establishing a tight connection between the brake piping of the truck and that of the trailer. The catch pin 25 during operation prevents undesired loosening or release of the swivel connection 24, 26.

The coupling must not be disconnected before the pressure is removed from the braking system. On loosening the cap member 22, the valve heads I I) and 20 are again urged upon their seats by action of the springs II and 2I, i. e. before the valve of the plug member is disposed outside of the braking fluid, so that even during the disconnecting operation no air is permitted to enter into the oil pressure braking system. Y

On disconnection the sleeve 4 is closed at its top by a cap (not shown) which is designed like the cap 22 but does not have an opening in the cover.

It should be noted that packing rings 29', 30, 3|, 32, 33 of a conventional type are provided between the various parts as shown. The lower valve casing 3 is locked in its position in the case I by a lock nut 34 and the pipe 1 is tightly secured to the valve casing 3 by a threaded sleeve 35.

It is also possible to provide guide members of another kind for the valves and the plug member. Moreover, it is possible to arrange the casing I so as to be vertical or inclined at an angle of less than 45 in relation to the vertical.

It will be understood that the field of application of the new coupling is not limited to motor vehicles but it can be used with good success wherever it is intended to couple hydraulic pressure pipes so as to be easily disconnectable while safely preventing the access of air.

While the invention has been described in detail with respect to a now preferred example and embodiment of the invention it will be understood by those skilled in the art after understanding the invention that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended, therefore, to cover all such changes and modifications in the appended claims.

What is claimed is:

1. A coupling for releasably interconnecting a pair of liquid carrying lines, having a rst member comprised of a reservoir disposed angularly to a horizontal plane, a liquid in said reservoir, a guide tube mounted in said reservoir, said tube having a smaller cross section than said reservoir, a valve casing secured to said reservoir and said guide tube adjacent the bottom of the reservoir and in communication with the guide tube, means on the end of said casing remote from said reservoir for attaching a liquid line thereto, valve means in said casing adjacent the end remote from said attaching means, perforations in the guide tube, some of said perforations being disposed beneath the surface of the liquid; a second member telescopically received in said guide tube, means on said guide tube and means on said second member releasably connecting the two members together, valve means mounted in the end of said second member adjacent said valve casing, means on said valve means in said members holding the valve means in open posi' tion when said members are connected, spring means in said casing and said second member urging the respective valve means toward closed position When said members are disconnected, the valve means in said members being disposed beneath the surface of the liquid when said members are connected and means on the end of said second member remote from said valve means adapted to connect the member to a liquid line.

2. A coupling for releasably interconnecting a pair of liquid carrying lines, having a first mem-y ber comprised of a reservoir adapted to be disposed angularly to a horizontal plane, said reservoir being adapted to contain a liquid, a guide tube mounted in said reservoir, said tube having a smaller cross section than said reservoir, a valve casing secured to said reservoir and said guide tube adjacent the bottom of the reservoir and in communication with the guide tube, means'on the end of said casing remote from said reservoir for attaching a liquid line thereto, valve means in said casing adjacent the end remote from said attaching means, perforations in the guide tube adjacent said casing so that the perforations will be located beneath the surface of a liquid in said reservoir; a second member telescopically received in said guide tube, meanson said guide tube and means on said second mem? ber releasablyv connecting the two members together, valve means mounted in the end of said' second member adjacent said valve casing, means on said valve means in said members holding the valve means in open position when said members are connected, spring means in said casing and said second member urging the respective valve means toward closed position when said members are disconnected, the valve means in said members being adapted to be disposed beneath the surface of a liquid in said reservoir when said members are connected and means on the end of said second member remote from said valve meansadapted to connect the member to a liquid line. I'.

3. A coupling for releasably interconnecting a pair of liquid carrying lines, having a irst member comprised of a reservoir disposed angularly to a horizontal plane, a liquid in said reservoir, a guide tube mounted in and concentric with said reservoir, said tube being of smaller diameter than said reservoir and having a portion extended beyond the top thereof, a valve casing secured to said reservoir and said guide tube adjacent the bottom of the reservoir and in communication l with the guide tube, means on the end of said casing remote from said reservoir for attaching a liquid line thereto, valve means in said casing adjacent the end remote from said attaching means, perforations in the portion of the guide 1 tube disposed within said reservoir, some of said perforations being disposed beneath the surface of the liquid; a second member telescopically received in said guide tube, means on said guide tube and means on said second member releasably connecting the two members together, valve means mounted in the end of said second mem- References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 755,325 Soutar Mar. 22, 1904 1,334,503 Olson Mar. 23, 1920 1,515,026 Frauenfelder Nov. 11, 1924 2,543,589 Newcomb Feb. 27, 1951 

